Patent GB-164057-A (GB)
Title: Improvements in automatic flute milling machines for reamers, taps, shafts and the like
IPC: B23C3/32
Filed: 1919-12-15
Abstract: 164,057. Hunt, H., Hunt, H. W., and Hunt, P., (trading as Hunt & Sons, H.). Dec. 15, 1919. Milling-machines; milling screws.-In a flutemilling machine for reamers, taps, shafts, &c. the mountings 10<a>, 10<b>, 10<c> for supporting the articles, are arranged side by side to mill simultaneously three small blanks, or two medium-sized blanks held in the outer mountings, or one large blank held in the central mounting, in which latter case the pivoted work slide may be set at an angle, and the sliding spindle 12, Fig. 5, formed with a spiral groove 12a to form similar grooves in the work. Means for indexing, withdrawing the work on the return stroke, varying the depth of groove, automatically stopping the feed in cases of incorrect operation of the indexing means, and means for holding the work on the spindle are also described. The bed 4 carrying the tailstock with centres 8, steady 5, and work support and driving means c, is mounted to slide vertically on arm 3 carried by a framing 1, which carries the cutter spindle 8. The means for vertically moving the bed 4 comprise (1) a cam 45 mounted on a frame 42 pivoted to the frame 2,' engaging an adjustably-mounted roller stop 46, and rotated from the shaft 11 so as to vary the depth of the flutes in the cutters if desired. On the pivoted portion 42 is a block 41 engaged by a trip lever 40 operated by stops 4<b>, 4<a> on the bed 4, to lower the bed for the return stroke and raise it again for the working stroke. The stops also operate a lever pivoted behind the lever 40, and coupled to a link 34 operating a sliding pinion 23 to engage the clutch 26 for low-speed feed motion, and clutch 25 for high-speed return motion of the pinion 22, feed-screw 21, and work table 4. The work is indexed during the return motion by the rotation of the spindle 11 which carries one centre c, and is geared to the other spindle, and is slidably connected to the ratchet wheel 13, supported on the arm 2<a> and operated by a crank 17 on shaft 18 driven through a friction clutch 54b when a catch 55 is.released from engagement with a projection 54<c> on the disc 54b by a pawl 56 operated by a link 57 coupled to the lever 40. On the return stroke the parts are re-set, a joint on the pawl 56 allowing of this. The clutch-operating lever 34 has a forked extension 34a which normally engages stops 39, on a pivoted lever 38, and prevents the engagement of the clutches but which can be moved by hand into position to release the lever 34, if a pin on the lever 38 can engage a slot in the collar 18a on the shaft 18, unless, through faulty operation of the indexing gear, the shaft 18 stops in the wrong position. A stop 43 takes the weight of the frame 2 in its lowered position. For spiral work the arm 2 may be swung to the right position on the arm 3, and a spiral grove 12a formed in the sliding spindle 12. Lathe and Like drivers.-The work is preferably driven by a plate 10<d> with clamping-screw 10<e> or slot to fit the large end of the work, and mounted between jaws 10<c> on the spindle end.